A Secure Transmission Scheme With Energy-Efficient Cooperative Jamming for Underwater Acoustic Sensor Networks

Underwater acoustic sensor networks (UASNs) face many security threats since they are deployed in open or even hostile environments. How to ensure the confidentiality of data transmission in the presence of eavesdroppers at unknown locations is an urgent problem. In this article, we first define the security coverage of the network. Then, a physical layer secure transmission scheme, named ST-CJ, which is based on self-assisting nodes with cooperative jamming signals, is proposed. With the allocated jamming transmission power, the proposed scheme takes advantage of the long propagation delays of underwater acoustic (UWA) signals to create collisions at the eavesdropper without affecting the reception of the legitimate user. In the ST-CJ, the transmission schedule and power level of each assisting node are jointly optimized. The goal is to maximize the coverage of the secure area in the network with minimal energy consumption. Both simulation and field test results demonstrate that the proposed scheme obviously reduces the interception ability of eavesdroppers, thus realizing the confidentiality of transmission.